Walter k



UNITED STATES WALTER K. MARVIN, oF NnW YORK, n. Y.

PATENT OFFICE.

IMPROVEMENT iN PROTECTING THE WALLS 0F FlRF-PRnOF SAFES FROM CORROSION.

Specification forming part of Letters Patent No. 40,799, dated December 1, 1863,

To all whom it may concern Be it known that I, WALTER K-LIARVIN, of New York city, in the county and State of New York, have invented certainnew and useful Improvements in'Fire-Proof Safes; and I hereby declare that the following is a full, clear, and exact description of the same.

Fire-proof safes and other similar fire-resisting structures are usually made of an iron or steel outer shell and an inner wooden shell, torming'between themselves a space or spaces, which are filled with a non-conductor of heat,

. composed of a substance generally containing water chemically combined, which on application of heat is liberated and-fills the interstices of the filling. substance or compound within the outerand inner shell with vapor or steam, rendering the safe incombnsuble, or

H nearly so. Most of these substances, however,

contain also water in suspension, which oozes through the joints of the safe and pervades the safe with moisture or dampness, destructive to books, papers, and other contents of the safe. Moreover, asa general thing these substances consist in or are composed of ingredients which readily combine with the iron .they are put in contact with, thus causing the corrosion and destruction of the most essential parts of a safe. To obviate these defects in, safes (numerous expedients were devised and resorted to, which, however, proved failures, since there is no fire-proof sale that is absolutely free from the objections before referred to.

The object of my invention is to protect the parts of the safe in contact with the filling thereof against corrosion, and to hermetically seal. or pack the joints, so that no moisture can escape from within the walls of the safe;

and l have accomplished this by the employment of liquid glassor quartz for coating the surface in contact with the filling and for lining the joints, substantially as hereinafter described.

To enable others to make and use this my invention, I shall now proceed to describe the manner in which the same may be carried iro etfect.

The outer shell, which is generally made of iron plates, united upon angle-iron running along the corners by means of bolts, rivets, screws, &c., is lirst thoroughly coated upon the interior with liquid glass or quartz, (pref-' erably that dissolved in caustic soda,) care being taken to fill the jointsi e., the corners formed by the convergence of two plates. The coat thus applied presents a rough appearance, and is liable to crumble. To form a smooth surface, and to more intimately unite the particles, I then slightly heat the shell. The quartz will then vitrifyi.' 0., the particles will fuse together-whereby the rugosities will disappear and form a smooth surface or glaze, giving the iron the appearance of being enameled. The joints, also, will be covered with a vitrified substance. The jointed iron shell will in this way belined, as it were, with a glass shell without joint. The inner shell, which is generally made of wood, is submitted to a similar glazing process; but it is applied to the outside, instead of the inside. The two I plates are then placed iii-position to receive theiilling,thejoints,whereverpracticable, ha v- ..ing previously been filled'with liquid quartz.

By thus proceeding a safe will be obtained free from moisture or dampness and not liable to corrode.

Having now described my invention, 1' v claim- The method herein described of protecting the parts of tire-proof safes from dampness or corrosion by the employment and application as a coating of the surfaces of the iron in contact with the filling, and for hermetically sealing the joints, of liquid quartz subsequcntly vitrified in the manner s bstantia-lly as hereinbeforc set forth.

In testimony whereofl have signed my name to this specification before two'subscribingwitnesscs.

WALTER K. MARVIN.

Witnesses:

A. loLLoK, I Joan S. l-lormuusnmn. 

